Natural Gas Price Forecasting by a New Hybrid Model Combining Quadratic Decomposition Technology and LSTM Model

Table 4

Characteristics of different models.

	Decomposition technique	Including the residual after the first decomposition	Quadratic decomposition technology
Random forest (model 1)
RNN (model 2)
ANN (model 3)
ELM (model 4)
LSTM (model 5)
EEMD-LSTM (model 6)	√
EEMD-VMD-LSTM (model 7)	√
VMD-LSTM (model 8)	√
VMD-Res.-LSTM (model 9)	√	√
VMD-EEMD-Res.-LSTM (model 10)	√	√	√